[Yukon Jack]

My three speed used to have lots of problems, especially when it got cold. I replaced it with a 4 speed but before that I did some adjustment on the linkage to get it shifting again.

To adjust the three speed you will need some sort of alignment rod, I used a nail cut to the right length. I also used a long board to keep the clutch pedal pressed in while doing the adjustments. The linkage adjustment is made under the hood on the steering column shaft. What you want to do is loosen up the nuts that tighten the guides on the shifting linkage. Get the tranny into neutral, which will have the two guides in line with each other. The guides have a small hole in them and there is also a raised notch on top of the steering column. Lay the nail on the notch and then move the guides until the nail slides through each guide. Then what I did was moved the linkage rods up and down to see how they cycle through the gears and then get back into neutral. Then I tightened the nuts so the guide is secure. Remove the alignment rod, ie the nail, and then cycle the tranny with the shift column in the cab. I had to do a little fine tuning to get the linkage right but it took all of 10 minutes once I figured out what I was doing.